The disclosure relates generally to distributed communications systems (DCS), and more particularly wideband digital DCSs employing programmable digital signal processing for scaling supported communications services.
Wireless customers are increasingly demanding wireless communications services, such as cellular communications services and Wi-Fi services. Thus, small cells, and more recently Wi-Fi services, are being deployed indoors. At the same time, some wireless customers use their wireless communication devices in areas that are poorly serviced by conventional cellular networks, such as inside certain buildings or areas where there is little cellular coverage. One response to the intersection of these two concerns has been the use of distributed antenna systems (DASs). DASs include remote antenna units (RAUs) configured to receive and transmit communications signals to client devices within the antenna range of the RAUs. DASs can be particularly useful when deployed inside buildings or other indoor environments where the wireless communication devices may not otherwise be able to effectively receive radio frequency (RF) signals from a source.
In this regard, FIG. 1 illustrates a distributed communications system (DCS) 100 that is configured to distribute communications services to remote coverage areas 102(1)-102(N), where ‘N’ is the number of remote coverage areas. The DCS 100 in FIG. 1 is provided in the form of a DAS 103. The DAS 103 can be configured to support a variety of communications services that can include cellular communications services, wireless communications services, such as RF identification (RFID) tracking, Wireless Fidelity (Wi-Fi), local area network (LAN), and wireless LAN (WLAN), wireless solutions (Bluetooth, Wi-Fi Global Positioning System (GPS) signal-based, and others) for location-based services, and combinations thereof, as examples. The remote coverage areas 102(1)-102(N) are created by and centered on RAUs 104(1)-104(N) connected to a centralized equipment 106 (e.g., a head-end controller, a central unit, or a head-end unit). The centralized equipment 106 may be communicatively coupled to a source transceiver 108, such as for example, a base transceiver station (BTS) or a baseband unit (BBU). In this regard, the centralized equipment 106 receives downlink communications signals 110D from the source transceiver 108 to be distributed to the RAUs 104(1)-104(N). The downlink communications signals 110D can include data communications signals and/or communication signaling signals, as examples. The centralized equipment 106 is configured with filtering circuits and/or other signal processing circuits that are configured to support a specific number of communications services (i.e., frequency communications bands). The RAUs 104(1)-104(N) are configured to receive the downlink communications signals 110D from the centralized equipment 106 over a communications link 112 to be distributed to the respective remote coverage areas 102(1)-102(N) of the RAUs 104(1)-104(N). The RAUs 104(1)-104(N) are also configured with filters and other signal processing circuits that are configured to support all or a subset of the specific communications services (i.e., frequency communications bands) supported by the centralized equipment 106. In a non-limiting example, the communications link 112 may be a wired communications link, a wireless communications link, or an optical fiber-based communications link. Each of the RAUs 104(1)-104(N) may include an RF transmitter/receiver (not shown) and a respective antenna 114(1)-114(N) operably connected to the RF transmitter/receiver to wirelessly distribute the communications services to user equipment (UE) 116 within the respective remote coverage areas 102(1)-102(N). The RAUs 104(1)-104(N) are also configured to receive uplink communications signals 110U from the UE 116 in the respective remote coverage areas 102(1)-102(N) to be distributed to the source transceiver 108.
Even though a DCS, such as the DAS 103 in FIG. 1, can address the issue of wireless customers using their wireless communication devices in areas that are poorly serviced by conventional cellular networks, DCSs are still not commonly deployed in buildings. Lack of appropriate in-building infrastructure coupled with the often prohibitively high installation and maintenance costs associated with a DCS means that many buildings still remain without adequate wireless communications service coverage. The issues of indoor network infrastructure cost and complexity are further compounded by the growth of new mobile technologies. For example, when a DCS is deployed as an in-building solution, the equipment in the DCS is configured with filters and other signal processing circuitry configured to support specific communications services and technologies (e.g., 2G, 3G, Wi-Fi, etc.). Thus, additional equipment that includes filtering circuits and/or other signal processing circuitry must be added for the DCS to support new communications services (i.e., new communications bands). Even more challenging is the fact that the addition of new communications services to a DCS may require modification to a network infrastructure and/or the installation of new equipment in the DCS.
Therefore, it is desired to provide a lower cost, in-building networking solution that enables the flexible addition of new communications services and/or modified communications services, including wireless communications services, to an existing installed DCS without undue tampering with the equipment of the installed DCS.
No admission is made that any reference cited herein constitutes prior art. Applicant expressly reserves the right to challenge the accuracy and pertinency of any cited documents.